In November, Rosetta will deploy a small robotic lander, Philae, which will steer itself onto the comet's surface before sending back images and data.

Together, Rosetta and Philae's instruments will conduct the most detailed analysis of a comet ever attempted.

Over the next two weeks it will remain the same distance from the comet, before edging closer until it settles just 18.6 miles (30 km) above the surface.

A primary initial goal will be to search for a suitable landing site for Philae, free as possible of holes, stones and craters. Sites where jets of gas erupt from the comet's interior will also have to be avoided, despite Philae being anchored down by harpoons and ice screws.

For the next 17 months Rosetta, a box-like structure just under 10 feet (3m) long with two wing-like solar panels, will remain close to the comet as it heads towards the Sun and heats up, throwing out increasing amounts of gas and dust.

Professor Richard Holdaway, director of RAL Space at the Rutherford Appleton Laboratory in Oxford, said: "This is an historic and hugely exciting moment for the Rosetta Mission.

Probe: the Rosetta's mission

"After 10 years of travel through space from Earth, Rosetta finally arrives at the comet and will land a unique shoe-box sized chemistry set designed and built by RAL Space and The Open University.

"We are very proud of our involvement and eagerly anticipate receiving the first results."

Information from the mission is expected to help scientists understand the origin of comets, the Solar System, and possibly life.

Comets are known to contain complex organic molecules rich in carbon, hydrogen, oxygen and nitrogen - the basic elements that make up the essential ingredients for life, nucleic and amino acids.

Many scientists believe comets may have helped to plant seeds of life on Earth.

Rosetta is named after the Rosetta Stone, a slab of basalt containing inscriptions that helped archaeologists decipher ancient Egyptian hieroglyphs.